1. Technical Field
The disclosure is directed to calibrating a wireless hands free system.
2. Related Art
Hands free systems may connect wireless users to a mobile telephone. The connection may use a wireless or physical technology to interface users to the phone. In vehicles, a cradle or a connector may interface the phone to an audio system. In use, signals received by the phone are passed through the hands free system before they are converted into audible sound. Speech from a near speaker (e.g., the driver) may be received from an input within the vehicle cabin. The input signal is passed from the hands free system to the phone which transmits the signals to a distant receiver.
Some phones compensate for signal distortions caused by the internal input or output devices. Some systems apply a fixed compensation to compensate for these distortions. In these applications, the systems may apply fixed compensation parameters. For different phones, suitable compensation parameters are predetermined.
A global compensation strategy may be adopted for a given model of phone. Unfortunately, variation may be common to identical models (e.g. due to production tolerances). In systems, software changes such as firmware updates may affect compensation quality just as unexpected noise or disturbances may affect quality.